Signatures of a gearwheel quantum spin liquid in a spin -½ pyrochlore molybdate Heisenberg antiferromagnet

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Yasir Iqbal - , Indian Institute of Technology Madras (IITM) (Author)
  • Tobias Müller - , University of Würzburg (Author)
  • Kira Riedl - , Goethe University Frankfurt a.M. (Author)
  • Johannes Reuther - , Free University of Berlin, Helmholtz Centre Berlin for Materials and Energy (Author)
  • Stephan Rachel - , Chair of Theoretical Solid State Physics, University of Melbourne, TUD Dresden University of Technology (Author)
  • Roser Valentí - , Goethe University Frankfurt a.M. (Author)
  • Michel J.P. Gingras - , Perimeter Institute for Theoretical Physics, University of Waterloo, Canadian Institute for Advanced Research (CIFAR) (Author)
  • Ronny Thomale - , University of Würzburg (Author)
  • Harald O. Jeschke - , Okayama University (Author)

Abstract

We theoretically investigate the lowerature phase of the recently synthesized Lu2Mo2O5N2 material, an extraordinarily rare realization of a S=1/2 three-dimensional pyrochlore Heisenberg antiferromagnet in which Mo5+ are the S=1/2 magnetic species. Despite a Curie-Weiss temperature (ΘCW) of -121(1) K, experiments have found no signature of magnetic ordering or spin freezing down to T∗≈0.5 K. Using density functional theory, we find that the compound is well described by a Heisenberg model with exchange parameters up to third nearest neighbors. The analysis of this model via the pseudofermion functional renormalization group method reveals paramagnetic behavior down to a temperature of at least T=|ΘCW|/100, in agreement with the experimental findings hinting at a possible three-dimensional quantum spin liquid. The spin susceptibility profile in reciprocal space shows momentum-dependent features forming a "gearwheel" pattern, characterizing what may be viewed as a molten version of a chiral noncoplanar incommensurate spiral order under the action of quantum fluctuations. Our calculated reciprocal space susceptibility maps provide benchmarks for future neutron scattering experiments on single crystals of Lu2Mo2O5N2.

Details

Original languageEnglish
Article number071201
JournalPhysical review materials
Volume1
Issue number7
Publication statusPublished - 13 Dec 2017
Peer-reviewedYes